QS60Style: Update placeholder texture to real one

Once the background texture has been created, update it to all widgets.

This corrects most cases where texture is used outside of QS60Style.
It is still possible to access the placeholder texture and draw it,
if:

    a) QPalette::Window is accessed before drawing even one widget
    b) Painting the texture happens without using QS60Style

Task-number: QTBUG-14910
Reviewed-by: Laszlo Agocs

4 files changed, 32 insertions, 11 deletions

diff --git a/src/gui/styles/qs60style.cpp b/src/gui/styles/qs60style.cpp
index c100330..a9e10a3 100644
--- a/src/gui/styles/qs60style.cpp
+++ b/src/gui/styles/qs60style.cpp
@@ -667,7 +667,7 @@ void QS60StylePrivate::setFont(QWidget *widget) const
     }
 }
 
-void QS60StylePrivate::setThemePalette(QWidget *widget) const
+void QS60StylePrivate::setThemePalette(QWidget *widget)
 {
     if(!widget)
         return;
@@ -752,7 +752,7 @@ void QS60StylePrivate::storeThemePalette(QPalette *palette)
 }
 
 // set widget specific palettes
-void QS60StylePrivate::setThemePaletteHash(QPalette *palette) const
+void QS60StylePrivate::setThemePaletteHash(QPalette *palette)
 {
     if (!palette)
         return;
@@ -3539,8 +3539,14 @@ extern QPoint qt_s60_fill_background_offset(const QWidget *targetWidget);
 
 bool qt_s60_fill_background(QPainter *painter, const QRegion &rgn, const QBrush &brush)
 {
+    // Check if the widget's palette matches placeholder or actual background texture.
+    // When accessing backgroundTexture, use parameter value 'true' to avoid creating
+    // the texture, if it is not already created.
+
     const QPixmap placeHolder(QS60StylePrivate::placeHolderTexture());
-    if (placeHolder.cacheKey() != brush.texture().cacheKey())
+    const QPixmap bg(QS60StylePrivate::backgroundTexture(true));
+    if (placeHolder.cacheKey() != brush.texture().cacheKey()
+        && bg.cacheKey() != brush.texture().cacheKey())
         return false;
 
     const QPixmap backgroundTexture(QS60StylePrivate::backgroundTexture());
diff --git a/src/gui/styles/qs60style_p.h b/src/gui/styles/qs60style_p.h
index 8c023bf..3628b27 100644
--- a/src/gui/styles/qs60style_p.h
+++ b/src/gui/styles/qs60style_p.h
@@ -554,7 +554,7 @@ public:
 
     static QPixmap frame(SkinFrameElements frame, const QSize &size,
         SkinElementFlags flags = KDefaultSkinElementFlags);
-    static QPixmap backgroundTexture();
+    static QPixmap backgroundTexture(bool skipCreation = false);
     static QPixmap placeHolderTexture();
 
 #ifdef Q_WS_S60
@@ -595,9 +595,9 @@ private:
 
     // set S60 font for widget
     void setFont(QWidget *widget) const;
-    void setThemePalette(QWidget *widget) const;
+    static void setThemePalette(QWidget *widget);
     void setThemePalette(QPalette *palette) const;
-    void setThemePaletteHash(QPalette *palette) const;
+    static void setThemePaletteHash(QPalette *palette);
     static void storeThemePalette(QPalette *palette);
     static void deleteThemePalette();
     static bool equalToThemePalette(QColor color, QPalette::ColorRole role);
diff --git a/src/gui/styles/qs60style_s60.cpp b/src/gui/styles/qs60style_s60.cpp
index e46c826..c5149a3 100644
--- a/src/gui/styles/qs60style_s60.cpp
+++ b/src/gui/styles/qs60style_s60.cpp
@@ -1391,7 +1391,7 @@ QPixmap QS60StylePrivate::frame(SkinFrameElements frame, const QSize &size, Skin
     return result;
 }
 
-QPixmap QS60StylePrivate::backgroundTexture()
+QPixmap QS60StylePrivate::backgroundTexture(bool skipCreation)
 {
     bool createNewBackground = false;
     TRect applicationRect = (static_cast<CEikAppUi*>(S60->appUi())->ApplicationRect());
@@ -1406,21 +1406,36 @@ QPixmap QS60StylePrivate::backgroundTexture()
         }
     }
 
-    if (createNewBackground) {
+    if (createNewBackground && !skipCreation) {
         QPixmap background = part(QS60StyleEnums::SP_QsnBgScreen,
             QSize(applicationRect.Width(), applicationRect.Height()), 0, SkinElementFlags());
         m_background = new QPixmap(background);
+
+        // Notify all widgets that palette is updated with the actual background texture.
+        QPalette pal = QApplication::palette();
+        pal.setBrush(QPalette::Window, *m_background);
+        QApplication::setPalette(pal);
+        setThemePaletteHash(&pal);
+        storeThemePalette(&pal);
+        foreach (QWidget *widget, QApplication::allWidgets()){
+            QEvent e(QEvent::PaletteChange);
+            QApplication::sendEvent(widget, &e);
+            setThemePalette(widget);
+            widget->ensurePolished();
+        }
     }
+    if (!m_background)
+        return QPixmap();
     return *m_background;
 }
 
-// Generates 1*1 red pixmap as a placeholder for real texture.
+// Generates 1*1 white pixmap as a placeholder for real texture.
 // The actual theme texture is drawn in qt_s60_fill_background().
 QPixmap QS60StylePrivate::placeHolderTexture()
 {
     if (!m_placeHolderTexture) {
         m_placeHolderTexture = new QPixmap(1,1);
-        m_placeHolderTexture->fill(Qt::red);
+        m_placeHolderTexture->fill(Qt::white);
     }
     return *m_placeHolderTexture;
 }
diff --git a/src/gui/styles/qs60style_simulated.cpp b/src/gui/styles/qs60style_simulated.cpp
index 77e0d0e..7223c6b 100644
--- a/src/gui/styles/qs60style_simulated.cpp
+++ b/src/gui/styles/qs60style_simulated.cpp
@@ -308,7 +308,7 @@ QPixmap QS60StylePrivate::frame(SkinFrameElements frame, const QSize &size,
     return result;
 }
 
-QPixmap QS60StylePrivate::backgroundTexture()
+QPixmap QS60StylePrivate::backgroundTexture(bool /*skipCreation*/)
 {
     if (!m_background) {
         const QSize size = QApplication::desktop()->screen()->size();